Engineering Commons^™

Meta Learning Recommendation System For Classification, Clarence O. Williams Iii

Theses and Dissertations

A data driven approach is an emerging paradigm for the handling of analytic problems. In this paradigm the mantra is to let the data speak freely. However, when using machine learning algorithms, the data does not naturally reveal the best or even a good approach for algorithm choice. One method to let the algorithm reveal itself is through the use of Meta Learning, which uses the features of a dataset to determine a useful model to represent the entire dataset. This research proposes an improvement on the meta-model recommendation system by adding classification problems to the candidate problem space with …

Neutron Energy Effects On Asteroid Deflection, Lansing S. Horan Iv

Theses and Dissertations

In the future, a hazardous asteroid will find itself on a collision course with Earth. It is an inevitability; the question is not if, but when. For asteroids of moderate size or larger, a nuclear device is one of humanity's only technologies capable of mitigating this threat via deflection on a timescale of less than a decade. This work examined how changing the output neutron energy from a nuclear device detonation affects asteroid deflection. The notional asteroid target was 300 meters in diameter and composed of silicon dioxide at a bulk density of 1.855 g/cm³. To calculate the …

Novel On-Chip Optical Modulator Designs, Mohamed Mahmoud Ibrahim Ibrahim Elsayed

Theses and Dissertations

The huge increments in data traffic and communication over the past few decades have pushed the conventional electronic communication systems to their physical limits in terms of data rate, bandwidth and capacity. The continuous shrinking of feature sizes, the increase in the microelectronic integrated circuits complexity, and the increasing demand for higher speeds and data rates have all stimulated seeking new technology to replace the currently present microelectronics industry rather than improving it. Photonics is one of the most likely candidates to answer this pursuit for its compatibility with the fiber optic industry, which has shown a great success in …

Error-State Estimation And Control For A Multirotor Uav Landing On A Moving Vehicle, Michael David Farrell

Theses and Dissertations

Though multirotor unmanned aerial vehicles (UAVs) have become widely used during the past decade, challenges in autonomy have prevented their widespread use when moving vehicles act as their base stations. Emerging use cases, including maritime surveillance, package delivery and convoy support, require UAVs to autonomously operate in this scenario. This thesis presents improved solutions to both the state estimation and control problems that must be solved to enable robust, autonomous landing of multirotor UAVs onto moving vehicles.Current state-of-the-art UAV landing systems depend on the detection of visual fiducial markers placed on the landing target vehicle. However, in challenging conditions, such …

Low-Cost Solid State Nanopore Biosensing Technology Towards Early Disease Detection, Julian Bello

Theses and Dissertations

Solid-state nanopore based biosensors are cost effective, high-throughput engines for single molecule detection of biomolecules, which is useful for detecting epigenetic modifications on DNA; one of these being the potentially cancerous hypo, or hypermethylation of CpG islands. Despite its immense potential in the realm of disease diagnostics, nanopore detection as it stands faces various limitations that inhibit it from widespread commercial use. These include the complex method of solid-state nanopore fabrication, fast DNA translocations through the pore causing poor resolution, and poor signal to noise ratio. The following work aims to improve the efficacy of the solid-state nanopore biosensing platform …

Mechanical And Structural Behavior Of As-Built And Post Treated Ti6al4v Lattice Structures Fabricated By Selective Laser Melting (Slm), Hala Ahmed Salem

Theses and Dissertations

Lattice structure is a type of cellular structures that is composed of repeatable unit cells, each of which is formed of interconnect network of struts. Lattices with different structures are gaining attention for their good mechanical properties for light weight applications. Selective laser melting (SLM), is one of the AM powder-bed fusion fabrication techniques. SLM is widely known for its capability for fabricating complex metallic structures such as lattice structures with high resolution. SLM process influence the microstructure and mechanical properties of fabricated parts. The used processing parameters influence the level of internal porosity within the fabricated parts which directly …

Novel Planar Wire-Grid Antenna Arrays For Automotive Radars Operating At 77 Ghz, Hossam Helaly

Theses and Dissertations

Automotive radars are the critical components for future driving assistance technologies. Nowadays, their usage is a constraint on the premium segment automobiles; however, there are intensive studies to facilitate these technologies to the lower segment. The main challenges that face automakers to develop new automotive radars are fabrication cost, compactness, bandwidth, and radiation properties. This research focuses on developing a novel class of planar antenna arrays, which operate at a frequency of 77 GHz. The proposed arrays can be fabricated using multilayered cheap printed circuit board lamination technology. The proposed antennas are arrayed using mixed wire-gridding and corporate arraying techniques, …

Fabrication Of Vascularized Scaffolds For The Treatment Of Spinal Cord Injury, Paul P. Partyka

Theses and Dissertations

The overall goal of the research presented here is to evaluate the efficacy of transplanting scaffolds containing central nervous system vasculature to repair spinal cord injury. There are three major phases of this effort: development of a three-dimensional model of central nervous system vasculature, transplantation of a pre-vascularized scaffold and optimization of the biomaterial used to deliver vasculature to the injured spinal cord. This research has produced the first ever compliant, three-dimensional (3D) blood-brain barrier (BBB) vessel. In order to create vascularized scaffolds appropriate for transplantation into a rat model of spinal cord injury, techniques to fabricate and spatially pattern …

Bioadhesive Hydrogel Composite Cell Carrier For The Repair Of The Degenerated Intervertebral Disc, Thomas Richard Christiani

Theses and Dissertations

Lower back pain (LBP) affects the worldwide population and can be attributed to the degeneration of the intervertebral disc (IVD). The IVD is composed of a central nucleus pulposus (NP), a peripheral annulus fibrosus (AF), and adjacent cartilage endplates (CEPs). IVD degeneration is characterized by proteoglycan loss, tissue dehydration, and decreased hydrostatic pressure. In this work, the use of an injectable bioadhesive hydrogel composite for replacement of the degenerated NP was investigated.

Results indicate that the composite exhibits similar mechanical properties to the NP, adheres to AF tissue, and supports encapsulated mesenchymal stem cell (MSC) differentiation toward an NP-like phenotype …

Development Of Iot Based Hybrid Autonomous Network Robots (Anr), Chimsom Isidore Chukwuemeka

Theses and Dissertations

The integration of wireless sensor networks (WSNs) and multirobot systems (MRS) represents an active research area supporting a wide range of applications. This is because it enables ubiquitous applications due to the robots' mobility and detection capabilities associated with its deployment. These systems have many benefits, such as perception with extended coverage that facilitate wider exploration and surveillance, efficiency in data routing, effective and reliable task environment management, etc. However, integrating two fields of research means dealing with a range of challenges such as using effective architecture for WSNs and MRS, efficient communication protocols within a network of sensors nodes …

Evaluating The Effectiveness Of Aerospace Materials, Vehicle Shape And Astronaut Position At Lowering The Whole Body Effective Dose Equivalent In Deep Space, Daniel K. Bond

Theses and Dissertations

As future crewed, deep space missions are being planned, it is important to assess how spacecraft design can be used to minimize radiation exposure. Collectively with shielding material, vehicle shape and astronaut position must be used to protect astronauts from the two primary sources of space radiation: Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE). GCRs, which are composed of low intensity, highly energetic, and fully ionized stable and meta-stable isotopes, are considered a chronic source of radiation risk to the astronauts. SPEs, which originate from solar coronal mass ejections, are composed mostly of high intensity protons that can …

Llogaritja E Aftësisë Mbajtëse E Tokës Në Kompleksi Banesor Në Gazi Babë-Shkup, Florijan Qazimi

Theses and Dissertations

Qëllimi i këtij punim bazohet në hulumtimin e vetive fiziko - mekanike të tokës ku do të mbështeten themelet dhe llogaritja e aftësisë mbajtëse të tokës duke shfrytëzuar dy metoda të krahasueshme: Metoda e Terzaku-të dhe Metoda e Mayorf-it. Si objekt për shqyrtim është marrë kompleksi banesor Ilievski Apartmants me lokacion në Komunën e Gazi Babës – Shkup, Maqedonia e Veriut. Një ndër hulumtimet e para që duhet të kryhet para se të fillojë ndërtimi i objektit janë shpimet gjeologo-gjeomekanike për nxjerrjen e parametrave gjeomekanik të cilët na shërbejnë për të konstatuar nëse toka ku do të bëhet ndërtimi është …

Extracellular Matrix Nanoparticles Effects On The Lung In Vivo, Brittaney E. Ritchie

Theses and Dissertations

Acute respiratory distress syndrome (ARDS) is a life-threatening condition that causes diffuse alveolar damage and a loss of the extracellular matrix (ECM). This leads to pulmonary edema and lung function deterioration. Our lab has created decellularized porcine lung, electrosprayed ECM nanoparticles that have been previously shown to have pro-regenerative capabilities in vitro.

In this study, the ECM nanoparticle effects on young murine lungs were tested in vivo. An ECM nanoparticle suspension, previously used for the in vitro studies, was aerosolized intratracheally into the lungs using a microsprayer. 24 hours later, the lung mechanics, bronchoalveolar lavage fluid, and histology …

Leveraging Peer-To-Peer Energy Sharing For Resource Optimization In Mobile Social Networks, Aashish Dhungana

Theses and Dissertations

Mobile Opportunistic Networks (MSNs) enable the interaction of mobile users in the vicinity through various short-range wireless communication technologies (e.g., Bluetooth, WiFi) and let them discover and exchange information directly or in ad hoc manner. Despite their promise to enable many exciting applications, limited battery capacity of mobile devices has become the biggest impediment to these appli- cations. The recent breakthroughs in the areas of wireless power transfer (WPT) and rechargeable lithium batteries promise the use of peer-to-peer (P2P) energy sharing (i.e., the transfer of energy from the battery of one member of the mobile network to the battery of …

Development Of An Anatomically And Electrically Conductive Brain Phantom For Transcranial Magnetic Stimulation, Hamzah A. Magsood

Theses and Dissertations

Transcranial Magnetic Stimulation (TMS) is a non-invasive technique for diagnostics, prognostic, and treatments of various neurological diseases. However, the lack of anatomically realistic brain phantoms has made the experimental verification of stimulation strength in the form of induced electric fields/voltages in the brain tissues an impediment to developing new TMS coils, stimulators, and treatment protocols. There are significant technological, safety, and ethical limitations to test the potential TMS treatment procedures or develop enhancements and refine them on humans or animals. This work aims to bridge the gap by introducing and developing an innovative manufacturing and fabrications process to produce a …

Development Of A Single Use Device Intended To Wash Blood Clot Debris From A Stent Retriever In The Operating Room, Shane Diller

Theses and Dissertations

Ischemic stroke is a life-threatening condition that requires immediate surgical intervention to remove the blood clot that is lodged in the blood vessels of the brain. Mechanical thrombectomy, performed by an endovascular surgeon, involves inserting a stent retriever, which deploys distally and attempts to capture the clot when dragged backwards. A complication prevalent in 50% - 67% of cases is that the blood clot is only partially removed and clings to the mesh framework of the stent. The operating surgeon must either clean the debris from the stent retriever, to be reinserted or throw the stent retriever away and open …

Reliable Navigation For Suas In Complex Indoor Environments, Andrew J. Fabian

Theses and Dissertations

Indoor environments are a particular challenge for Unmanned Aerial Vehicles (UAVs). Effective navigation through these GPS-denied environments require alternative localization systems, as well as methods of sensing and avoiding obstacles while remaining on-task. Additionally, the relatively small clearances and human presence characteristic of indoor spaces necessitates a higher level of precision and adaptability than is common in traditional UAV flight planning and execution. This research blends the optimization of individual technologies, such as state estimation and environmental sensing, with system integration and high-level operational planning.

The combination of AprilTag visual markers, multi-camera Visual Odometry, and IMU data can be used …

Automatic Hip Analysis Suite, Nathan J. Veilleux

Theses and Dissertations

Image recognition and computer vision are becoming increasingly useful for diagnostic and surgical planning purposes. Analyses of patient morphology can be performed much more quickly and reliably with algorithmic assistance. Traditional measurements of the hip involve visual inspection of patient radiographs or hand calculation with software assistance. In the most extreme cases, estimates of bone orientation are made via palpation of a patient’s hip. There is the possibility for significant improvements in reliability if measurements can be made in the absence of human interpretation. As many of these techniques require CT scans as a prerequisite, all of the necessary information …

Redox-Active Porous Organic Materials For Electrochemical Energy Storage Applications, K. Shamara Weeraratne

Theses and Dissertations

As the demand for renewable energy technologies grows, so does the need for cheaper, more efficient rechargeable batteries to store the energy. While lithium-ion battery (LIBs) technology is well established, it suffers from limited lithium supplies. Furthermore, the highly toxic transition metals used in the electrodes places a huge burden on the environment. Therefore, replacing lithium with more economical sodium metal in rechargeable batteries (i.e. sodium-ion batteries, SIBs) has garnered considerable attention. Despite the fact that sodium and lithium share similar electrochemical properties, which may cause the transition from lithium to sodium easier, the larger ionic radius of Na^{+ …}

Application Of Immobilized Palladium Monolithic Catalysts In Suzuki-Miyaura And Tsuji-Wacker Redox Reactions, Sajjad Ghobadi

Theses and Dissertations

Herein, a wholistic analysis of the viability of monolithic catalysts for redox reactions is presented. The interdisciplinary approach taken in this systematic study included preparation and investigation on Pd-on-carbon monoliths as catalysts in a flow and electrochemical settings.

The Suzuki-Miyaura reaction-focused study led to rational design, preparation, and successful application of Pd⁰-on-graphene oxide (GO) monolithic catalysts in flow conditions. In this study a combination of chemical reduction, freeze-casting, and vapor-phase reduction processes was applied to Pd-GO structures leading to the preparation of these monoliths. The Suzuki flow synthesis reactions revealed that the monolithic structure led to significantly improved …

Thermal Atomization Due To Boiling During Droplet Impingement On Superhydrophobic Surfaces, Preston Todd Emerson

Theses and Dissertations

Superhydrophobic (SH) surfaces are characterized by their extraordinary water repellent qualities. When water comes in contact with these surfaces, it beads up and rolls around. This phenomenon is due partially to surface chemistry which promotes weak adhesive forces between liquid and solid. However, micro- and nanoscale surface roughness also plays a crucial role by trapping air beneath the liquid, reducing liquid-solid contact. Many advantages of these surfaces have been identified, including drag reduction and self-cleaning properties, and the body of research regarding them has grown rapidly over the past few decades.This thesis is concerned with water droplets impinging superheated, superhydrophobic …

Quantification And Modeling Of Bladder Biomechanics Mechanisms Linking Spontaneous Rhythmic Contractions And Dynamic Elasticity To Detrusor Overactivity, Zachary E. Cullingsworth

Theses and Dissertations

Overactive bladder (OAB) is a chronic condition affecting approximately 20% of adults in the United States. Detrusor overactivity (DO) is the presence of non-voiding contractions in the detrusor (bladder) muscle during filling and is present in some individuals with OAB. DO is currently identified visually during a urodynamics (UD) study involving pressure catheters and filling and voiding of the bladder to evaluate function. UD provides limited subtyping of DO, and an incomplete understanding of mechanisms contributing to OAB.

Aim 1 of this study was to develop objective tools to quantify, subgroup and better understand …

Electric Field Control Of Fixed Magnetic Skyrmions For Energy Efficient Nanomagnetic Memory, Dhritiman Bhattacharya

Theses and Dissertations

To meet the ever-growing demand of faster and smaller computers, increasing number of transistors are needed in the same chip area. Unfortunately, Silicon based transistors have almost reached their miniaturization limits mainly due to excessive heat generation. Nanomagnetic devices are one of the most promising alternatives of CMOS. In nanomagnetic devices, electron spin, instead of charge, is the information carrier. Hence, these devices are non-volatile: information can be stored in these devices without needing any external power which could enable computing architectures beyond traditional von-Neumann computing. Additionally, these devices are also expected to be more energy efficient than CMOS devices …

A Longitudinal Study Of The Influence Of A Stem Career Planning Course And Perceived Stress On Career Search Self-Efficacy And Retention In Engineering Undergraduate Students, Autumn Randell

Theses and Dissertations

This study investigated a) the influence of a STEM career planning course on undergraduate engineering students’ career search self-efficacy, b) the influence of perceived stress on building students’ career search self-efficacy, and c) the relationship career search self-efficacy had in predicting students’ odds of persistence in an engineering major. The researcher analyzed students’ week 1, week 6, and week 14 scores of career search self-efficacy and perceived stress. Data were collected from the Spring 2019 and Fall 2019 cohorts of a STEM career planning. As a result, the analysis included (N = 286) undergraduate engineering students. Repeated measures multilevel …

The Effect Of Intermittent Theta Burst Stimulation On Biceps Corticomotor Excitability In Non-Impaired Individuals And Individuals With Tetraplegia, Blaize Majdic

Theses and Dissertations

Neuromodulation of the primary motor cortex (M1) in pair with physical therapy may be a promising method for improving motor outcomes after spinal cord injury (SCI). Increased excitability of the corticospinal motor pathways (i.e. corticomotor excitability) has shown to be associated with improved motor learning and skill acquisition. Intermittent theta burst stimulation (iTBS) is a form of non-invasive brain stimulation which can increase corticomotor excitability, as measured by an increase in the amplitude of motor evoked potentials (MEPs). However, the ability for iTBS to increase the corticomotor excitability of proximal muscles such as the biceps, and muscles affected by spinal …

Generation Of Warm Dense Plasma On Solar Panel Infrastructure In Exo-Atmospheric Conditions, Harrison C. Wenzel

Theses and Dissertations

The use of a weaponized thermo-nuclear device in exo-atmospheric conditions would be of great impact on the material integrity of orbiting satellite infrastructure. Particular damage would occur to the multi-layered, solar cell components of such satellites. The rapid absorption of X-ray radiation originating from a nuclear blast into these layers occurs over a picosecond time scale and leads to the generation of Warm Dense Plasma (WDP). While incredibly difficult and costly to replicate in a laboratory setting, a collection of computational techniques and software libraries may be utilized to simulate the intricate atomic and subatomic physics characteristics of such an …

Higher Tensile Forces Across Cellular Junctions And An Intact Nuclear Linc Complex Is Required For Epithelial Function And Stability, Fnu Vani Narayanan

Theses and Dissertations

Recent advances in three-dimensional (3D) cell culture systems have provided key insights into the understanding of biochemical and physiological states of native tissue. A significant progress in the field of mechanobiology involves measuring cellular traction forces in a more native 3D environment. However, the effects of mechanical forces exerted across cellular junctions and the nuclear LINC complex, in an organized 3D system has not been investigated thus far. Epithelial cells spontaneously form acini (also known as cysts or spheroids) with a single, fluid-filled central lumen, when grown in 3D matrices. The size of the lumen is dependent on apical secretion …

Magnetic Refrigerator Device Based On La (Fexcoysi1-X-Y)13, Khushar Javed

Theses and Dissertations

Particles of Lanthanum-iron-silicide, La (Fe_xCo_ySi_1-x-y)₁₃exhibit different magnetic properties when stored in air compared to the same stored in water. The sample with a nominal composition of La(Fe0_.842Co_0.073Si_0.084)₁₃was prepared by arc-melting from elements under argon atmosphere. In recent years, there has been research conducted on different processes that could drastically reduce energy costs of cooling and replacing gas compressors with magnetocaloric materials. Magnetization measurements were carried out on this magnetocaloric material to characterize it in order to design magnetic refrigerator device based on it. The …

Development Of Near-Real Time Material Detection And Analysis By Coupling Electrochemical & Optical Spectroscopy Methods For Molten Salt Systems, Hunter Andrews

Theses and Dissertations

For both pyroprocessing and molten salt reactors (MSRs), it is desirable from a process control and nuclear safeguards perspective to monitor the species in the molten salts for material accountancy. Many traditional monitoring techniques, even simple salt sample retrieval, are time exhaustive or rendered useless for these systems due to the high thermal loads, high radiation zones, and corrosive nature of molten salts. Therefore, the main motivation for this work is the need for an online monitoring system for a molten salt system that is robust enough to handle the extreme environment yet deliver quantifiable salt concentrations. The intent of …

Peridynamic Approaches For Damage Prediction In Carbon Fiber And Carbon Nanotube Yarn Reinforced Polymer Composites, Forrest E. Baber

Theses and Dissertations

Aerospace structures are increasingly utilizing advanced composites because of their high specific modulus and specific strength. While the introduction of these material systems can dramatically decrease weight, they pose unique certification challenges, often requiring extensive experimental testing in each stage of the design cycle. The expensive and time-consuming nature of experimental testing necessitates the advancement of simulation methodologies to both aid in the certification process and assist in the exploration of the microstructure design space.

Peridynamic (PD) theory, originating from Sandia National Lab’s in the early 2000’s, is a nonlocal continuum-based method that reformulates the equation of motion into an …